SPM Question Year 2010

9.  a)          The weight of a body is the gravitional force acting on the body.


     b)   (i)  - The weight of the father is higher than the weight of the boy.
                 - The volume of water displaced by the father is bigger than the volume of water                                                             
                    displaced by the boy.
                 -The bouyant force that acts on the father is greater than the boy.
              
           (ii)   a) When the volume of the water displaced increases,the bouyant force increases.
                  b) When the weight of the water displaced increases,the buoyant force increases.


           (iii)   Archimede's principle 


     c)          - When the wooden block is submerged in water,the buoyant force is
                     greater then it's weight.
                  - Hence,the buoyant force pushes the block upwards.
                  - This occurs until the block reaches the surface when the weight of 
                     water is displaced


     d)    (i)  The shape of the raft
                  -Use steamline shape to reduce water displaced.


            (ii) The material used for the raft
                  -use light material like bamboo to make the raft float.


            (iii) The size of the raft
                 - large size of raft is easier to accomodate participant.


            (iv) The design of the raft 
                  - tie the bamboo layers.Put motor at the end of the raft to increase the speed 
                    of the raft.